Burglar alarm



June l5, 1948. T. M. CADENHEAD 2,443,553

' v BURGLAR @LARM Filed Nov. 2, 1944 2 Sheets-Sheet 1 I N VEN TOR.Tfe//ZKQQZO/zeed w A C T. M. CADENHEAD BURGLAR ALARM June 15, 1948.

" Filed Nov.` 2, 1944 2 Smets-Sheet 2 t N VE N TOR. 7' a/fzasf @QQ/aaaiPatented June 15, 1948 UNITED STATES PATENT OFFICE BURGLAR ALARMk*Thomas M. Cadenhead, Waycross, Ga.

Application November 2, 1944, Serial No. 561,593

1 Claim.

.The invention relates-t a burglar alarm, and more especially to acombined latch and burglar alarm.

The primary object of the invention .is the provisionA of a device ofthis character, wherein closures, such as window sashes can be latchedclosed, and when an attempt is made to raise the lowermost one or lowerthe uppermost one, an alarm will be automatically sounded, therebysignalling that an unauthorized entry is being made to an enclosure, thedevice being of. novel construction and unique in its application forservice.

Another obj ect of the invention is the provision of a device of thischaracter, wherein in the `working. thereof, it affords a dual purpose,namely, the latching of the sashes, and the sounding of an alarm, when afalse entry is attempted to an enclosure.

A further obj-ect of the invention is the provision of a device of thischaracter, wherein the alarm is manually controlled in the turning onvor off thereof, and when turned on, it automatically operates for analarm when a false entry to an enclosure is attempted.

A still further object of the invention is the provision of a device ofthis character, which is simple in construction, thoroughly reliable andefficient in operation, strong, durable, readily and easily mounted inplace, compact, it being possessed of few parts, readily and easilycon-` trolled, and is inexpensive to manufacture and install.

With these and other objects in view, the invention consists in thefeatures of construction, combination and arrangement of parts as willbe hereinafter more fully described, illustrated in the accompanyingdrawings, which show the preferred embodiment of the invention andpointed out in the claim hereunto appended.

In the accompanying drawings* Figure 1 is a fragmentary verticalsectional view through a window frame, showing the upper and lowersashes thereof closed with the device constructed in accordance with theinvention applied.

Figure 2 is a view similar to Figure 1 showing the lower sash partlyraised for the automatic operation of the device.

Figure 3 is a fragmentary horizontal crosssectional view through theupper sash showing the device in top plan.

Figure 4 is a detail elevation of the latch assembly.

Figure 5 is a vertical transverse sectional view through the alarmassembly.

Figure 6 is a sectional view taken on the line 6-6 of Figure 5 lookingin the direction of the arrows.

Figure 7 is a fragmentary top plan view thereof.

Figure 8 is a perspective View of the control cam for the alarm.

Figure 9 is an edge view thereof.

Figure 10 is a fragmentary sectional view through the alarm.

Figure 11 is a further fragmentary sectional view thereof.

Similar rreference characters indicate corresponding parts throughoutthe several views in the drawings.

Referring to the drawings in detail, A designates ygenerally a portionof a window frame, B a portion of the lower sash therein and C a portionof the upper sash therein, respectively. The sashes B and C are slidablymounted in the window frame A in the usual wellkr1own manner, and inassociation therewith is the device D constructed in accordance with theinvention and hereinafter fully described. The alarm D comprises asubstantially rectanf gular shaped casing I having a removable coverplate II, and Within this casing is arranged a spring powered motormechanism, including a frame I2 for a train of clock gearing I3 drivenfrom a winding spring I4, its winding arbor I5 being extended exterorlyof the cover plate II and has attached thereto a double wing winding keyI6. The gearing I 3 operates a ratchet toothed escapement wheel I'I withwhich is associated an escapement dog I8, its rocking shaft or arbor I9being tted with a clapper arm 20, carrying a clapper head or knob 2l forthe sounding of the alarm bell 22. The bell 22 is supported on acenterpost 23 secured in place at the outer end wall 24 of the casing Iil. The other inner end wall 25 of the casing I0 is secured to thevertical run of the window frame A, so that the casing Ill will bedisposed in a horizontal plane just slightly below the parting rail 26of the lower sash B, to have the key l@ disposed vertically uppermost tothe cover plate I I, as best seen in Figures 1 and 2 of the drawings.

The master peripherally toothed driving gear 21 of the gear train isnormally engaged by a manually releasable locking detent 28 formed atthe hook end 29 of a throw stem 30, which passes outwardly of the casingI D through the cover plate II centrally of a cam ring 3I fixed to thelatter at 32. The outermost end of this stem 30 has swiveled thereon aturning sleeve 33 having a finger knob 34, and 'also provided with ahorn L35 for riding the cam ring 3|, which when at the high area of thelatter brings the detent 23 into engagement with the gear 21 lforlocking the same against movement, and when the horn 35 is at the lowarea of the cam ring 3l, the detent 28 will be disengaged with the saidgear 21 for activity of the alarm in a manner presently described. Thehook end 29V is acted upon by a leaf spring 3E which holds the horn atall times in contact with the cam ring 3l. Adjacent to the ring 3| andallocated to the high and low yareas of the cam are the identicationmarkings on and om respectively, so that it can be determined Whether ornot the spring motor is on or oil? for activity or non-activity of thealarm under pre.- scribed conditions.

On the parting rail 28 of the lower sashy B at its side next to thecasing l is a pivot bearing N for the pivot crank 39 of an- L-shaped.combined latching and alarm releasing trigger 40, the; U -shapedhook-like latching. extent. 4.1 thereof bridges the parting rail 2S- ofthe lower sas-h B, for detachable engagementl in a hooking eye 42 fixed`in thel parting rail- 43 of the upper sash C, while the alarm releasingextent M of this, trigger 40 is designed to be seated between the.double wings 45 of the; winding. key Hi, as best. seen in Figures- 1.and 3 of the drawings. This seating of the extent 44 is the normalposition thereof with respect tov the key t6, but when an attempt ismade to effect a false entry to an enclosure through the window frame Aby a slight. raising of thev lower sash B- or lowering of the. uppersash C, the trigger Ml will be caused to rock, assuming the positionbest shown in Figure 2. of the dra-wings, and thus become unseated frombetween the wings 45 of the key i6, which results in releasing thelatter.. If the alarm mechanism is unlocked by the detent- 2.8 foractivity then. the bell 22 will be sounded thus issuing an alarm toindicate a false entry is being attempted through the Window frame A.The extent. 4| is readily detachable from the hooking eye 4:2, when itis desired to unlatch the sashes and also disconnect the alarm operationtherefrom.

What is claimed is:

In a burglar alarm for windows of the double hung type having upper andlower sash slidable in a Window frame with parting rails at the meetingpoint of the sash, an alarm device mounted on the window frame having aclock-like mechanism with a bell and having a winding key with separatedupwardly extending wings, a latch member having extending ends, abearing plvotally mounting the latch member onthe inner face of theparting rail at the upper end of the lower sash, one end of said latchmember being L-shaped in plan providing a trigger and having aprojection at the end positioned between the wings of the winding key ofthe alarm mechanism retaining said mechanism inoperative, the other end.of said latch member being U-shaped in elevation with a short armextending from the bearing and a longer arm extending over the partingrail of the lower sash and having a hook there- 011 and an eye on theparting rail'` at' the lower end of the upper sash in which the saidhook ci the latch member is positioned whereby' upon raising the lowersash or lowering the upper sash the latch member arrests the openingmovement locking the sash and releases the alarm mecha:- nism.

THOMAS M. CADENHEAD;

REFERENCES CITED The following references are of record in the iile ofthis patent:

UNITED STATES PATENTS Number Name Date 53,239 Winans Mar. 13, 1866301,862 Chase July 1151, 1884 348,781 Sane Sept. 7, 1886 l196,519Krumscheid 2, 11893 606,862 Gray July 5, 1898 870,063 Uhlmann Nov. 5,19057 874,202 Humason Dec. 175,51907 1,040,156 Cunningham Oct. 1, 19.1211,253,986 Larson Jan.4 l5, 19518 1,830,550 Pettyjohn Nov.. 3, 1.9311,849,918 Fisher et al Mar; 15, 1932 2,084,841 Fleishmann Junei- 22.,1932

